diff --git a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
index 078fb7889593..5d1e49d823c9 100644
--- a/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
+++ b/Documentation/devicetree/bindings/usb/snps,dwc3.yaml
@@ -240,7 +240,7 @@ properties:
     description:
       High-Speed PHY interface selection between UTMI+ and ULPI when the
       DWC_USB3_HSPHY_INTERFACE has value 3.
-    $ref: /schemas/types.yaml#/definitions/uint8
+    $ref: /schemas/types.yaml#/definitions/string
     enum: [utmi, ulpi]
 
   snps,quirk-frame-length-adjustment: